PROSPECTIVE EVALUATION OF MIGRATION, COMPLICATIONS AND UTILITY OF FIDUCIAL PLACEMENT FOR CYBERKNIFE TREATMENT IN HEPATOBILIARYTUMORS

Abstract

Background: Hepatocellular carcinoma (HCC) is the most common primary tumor of the hepatobiliary system. The Cyberknife represents a new, frameless stereotactic radiosurgery system with image-guided radiation delivery using fiducials as markers to overcome the movement of intra-abdominal organs due to respiration. However fiducial placement and treatment have its issues such as migration and other complications.

Objectives: We evaluated the accuracy and feasibility of fiducial placement under image guidance and complications during and after placement such as migration including pain score.

Materials and Methods: A prospective observational study was carried out on 36 subjects with clinically and radiologically diagnosed hepatocellular carcinoma receiving Cyberknife based stereotactic based radiotherapy (SBRT). Fiducial markers for SBRT were introduced under percutaneous Ultrasound (US) or CT guidance. After placement, fiducial migration rate, pain score, fiducial placement related complications were noted during and after therapy. IBM SPSS statistical software version 21 was used for statistical analysis.

Results: 8.4% had gross fiducial displacement on the day of the procedure. 90.9% had minimal migration during treatment.There was no gross migration seen during treatment or post-treatment. Post fiducial placement, 2.8 % had a major complication in the form of liver decompensation resulting in death while minor complications were observed in 13.9%. The average pain score was minimal (0.86) post fiducial placement. There was no pain in any of the patients during or after the treatment.

Conclusion: Image-guided implantation of fiducial markers in the liver for stereotactic body radiation therapy had a high technical success rate and is a safe procedure with rare complications.There is minimal fiducial migration seen during the treatment. But being a descriptive study with a small sample size limits the generalizability of our study findings.